The ultrahigh flux polarized cold neutron spectrometer PANDA of the FRM-IIreactor

At present the high flux research reactor FRM-II is under construction in G arching, Germany. As part of the first set of instruments, a triple axis sp ectrometer is under construction at the cold source in the reactor hall. Th is instrument will be mainly used to study inelastic magnetic phenomena in condensed matter physics. Besides an unpolarized beam setup, PANDA is equip ped with devices allowing full polarization analysis. This instrument large ly profits from its vicinity to the reactor, and uses state of the art neut ron optics. Thanks to the large focusing Heusler monochromator and analyzer the neutron flux of the polarization setup will be of the same magnitude a s that of an unpolarized beam at a high flux reactor. The accessible energy and Q ranges will be extremely large due to an advantageous flux distribut ion of the cold source and a particular construction of the beam tube and t he biological shielding which contain supermirror neutron guides. A resonan t spin echo device, used to perform line shape analysis of dispersive excit ations, will complete the extensive array of equipment, available on PANDA. (C) 1999 American Institute of Physics. [S0021-8979(99)21708-2].